lithosphere Flashcards
explain the formation of a corrie
(excluding glacier in a hollow)
The weight of the glacier
pushes downwards causing rotational sliding, this over deepens the hollow. As the glacier reaches the edge of the hollow friction causes the glacier to loose momentum and drop its moraine. This can
form a rock lip. As the glacier leaves the hollow and begins to melt a tarn can be left. An example of a Corrie is Brown Cove.
Explain the formation of a glacier in a hollow
Snow collects in a north-facing mountain hollow. As it accumulates it compresses into neve and eventually into ice. This forms a glacier. Gravity causes the glacier to move downhill, eroding the hollow as it does so. As it moves downhill it freezes onto the bedrock and pulls away loose
rock fragments eroding away the hollow, this process is known as plucking. Rock fragments become embedded in the glacier and wear away the floor like sandpaper, in a process known as abrasion.
[Freeze than weathering occurs when water seeps into cracks in the rock and freezes and melts repeatedly, the constant expansion and contraction breaks away small rock fragments.]
explain the formation of an Arete
(excluding glacier in a hollow)
An arete is formed when two corries form back to back creating a knife like ridge. An example of an arete is Striding Edge
explain the formation of a Pyramidal Peak
(excluding glacier in a hollow)
A pyramidal peak is formed when three or more corries form back to back. A pyramidal peak is a mountain with a narrow, pointed summit. An example of a pyramidal peak is Matterhorn.
Explain the formation of a glacier in a valley
Snow collects in a valley at high attitude . As it accumulates it compresses into neve and eventually into ice. This forms a glacier. Gravity causes the glacier to move downhill, eroding the hollow as it does so. As it moves downhill it freezes onto the bedrock and pulls away loose
rock fragments eroding away the , this process is known as plucking. Rock fragments become embedded in the glacier and wear away the floor like sandpaper, in a process known as abrasion.
[Freeze thaw weathering occurs when water seeps into cracks in the rock and freezes and melts repeatedly, the constant expansion and contraction breaks away small fragments of rock.]
Explain the formation of a U-shaped Valley
(excluding a glacier in a valley)
After glaciation once the glacier has melted a U-shaped valley is left with steep sides and a wide flat floor. An example of a U-shaped valley is Glen Coe.
Explain the formation of a hanging valley
(excluding a glacier in a valley)
A hanging valley is formed when a large glacier is joined by a smaller tributary glacier. The large glacier erodes more quickly than the smaller glacier. After glaciation the large glacier leaves a large U-shaped valley and the smaller glacier leaves a smaller u-shaped valley suspended above it. An example of a hanging valley is Bowen Falls.
Explain the formation of a ribbon lake
(excluding a glacier in a valley)
A ribbon lake is formed when a glacier moves down a v-shaped valley with bands of hard and soft rock, eroding the soft rock more quickly. This quicker erosion causes the soft rock to become deeper quicker. Moraine that has built up over time will be dropped at the front of the glacier when it melts, leaving a lake. An example of a Ribbon lake is Lake Windermere.
Formation of a glacier
(glacial deposition)
Snow collects in a river valley at high altitudes, as it accumulates it compresses into neve and eventually into ice. This forms a glacier. Gravity causes the glacier to move downhill.
Explain the formation of Terminal Moraine
(excluding the glacier)
As the glacier moves downhill it pushes sediment in front of its snout like a bulldozer. The material being pushed by the glacier is unsorted. As the glacier reaches lower altitudes and higher temperatures, it begins to melt causing it to lose power and drop its moraine. Terminal moraine is a ridge running across the valley which consists of glacial deposits. It marks the furthest point that the glacier reached. After the ice has retreated, terminal moraine may dam the valley forming a ribbon lake. After the terminal moraine, an outwash plain may be formed.
Explain the formation of Eskers
(excluding the glacier)
An esker is a steep-sided long winding ridge, made up of gravel and sand. It is formed when a river of meltwater runs through a glacier. The river deposits sorted material that it can no longer carry. The material is small and rounded by abrasion in the water. When the glacier melts the river is also lost from the
landscape and the esker is left.
Explain the formation of Drumlins
(excluding the glacier)
Drumlins are large mounds of unsorted material left on landscapes by glaciers. They are formed when the glacier becomes overloaded with sediment, therefore causing them to deposit material. As the glacier moves over the deposited sediment, it streamlines the material. Further movement of the ice can
reshape drumlins. The steep ‘Stoss’ slape faces up-valley and the more gently sloping ‘lee’ slope faces down-valley. This means that the narrow end of a drumlin can show us which direction the glacier was going. Drumlins are
found in large groups which are called swarms.
Describe possible land use conflicts in a glaciated area
____________________________
Explain the solutions used to manage these conflicts and their effectiveness
glaciated upland
____________________________________
Explain the formation of a wave cut platform
Wave-cut platforms and notches are formed on cliff face by hydraulic Action, which is when the force of the waves forces air into cracks the rock creating an explosive blast which ween and loosens rock fragments. And solution which occurs when carbonic acid in sea water dissolves rock such as limestone and chalk. The rock above overhang the notch and as
erosion continues the notch is enlarged until the overhang collapses due to gravity. The new cliff face is then eroded and with time the cliff retreats inland leaving a gently-sloping rock surface called a wave-cut platform, which extends out to sea away from the cliff. The platforms abraded by rock materials, with rock pools and pot holes forming which are evident at low tide.
Explain the formation of headlands and bays
Headlands and bays are formed when alternating bands of hard and soft rock appear at a coastline. The hard rock is more resistant to erosion than the soft rock, which breaks down more quickly due to coastal erosion. This is called differential erosion. Erosion takes place due to processes such as hydraulic action-which occurs when the force the waves pushes air into cracks in the rock creating an explosive blast which weakens and loosens rock fragments - and solution - which occurs when carbonic acid in sea water dissolves rock such as limestone and chalk. This leaves headlands, where hard rock juts into the sea and bays occur in the sheltered areas between
the soft rock which has been worn away. Within the bays constructive waves may
a small beach.
Explain the formation of a Stack
Rocks contain weak points that are more easily eroded. This occurs due to the processes of hydraulic action -where the force of the waves into cracks in the rocks creating on explosive blast which weakens and loosens rock
fragments. And solution - which occurs when carbonic acid in sea water dissolves rock such as Limestone and chalk. Over time these weak
points are enlarged to form sea caves. Erosion may occur on both sides of the headland cutting through to fam an archway. The base of the arch is undercut, and the arch roof eventually becomes unsupported. This causes it to collapse due to gravity, forming a stack. An example of a stack is Old Harry.
Explain the formation of a spit
Sand spits are formed by the process of longshore drift. Which is a zig-zag movement of the waves. Swash is were waves push material up the beach at an angle due to prevailing wind. The returning backwash is dragged back down the beach at right angles
due to gravity. Spits form when there is a change in direction on a coastline allowing a build up to appear above the water. The spit
develops as long as the supply of deposits is greater than the amount of erosion. An example of a spit is Spurn Head.
Explain the formation of a bar
Sand bars are formed by the process of longshore drift which is a zig-zag movement of the waves. Swash is were waves push material up the beach at an angle due to prevailing wind. The returning backwash is dragged back down the beach at right angles due to gravity. form when there is a change in directions
coastline allowing a build up to appear above the water. If a spit reaches the other side of a bay then a sand bar is formed. An example of a sand bar is Slapton Sands.
explain the formation of a tombolo
Tombolos are formed by the process of longshore drift the zig-zag movement of the waves. Swash is where the push material up the beach at an angle due to prevailing wind.
The returning backwash is the waves that drag material back down the beach at right angles due to gravity. Tombolos form where a change in direction of a coastline allows a sheltered area for deposition. Material slowly builds up to appear above the water. When a spit joins onto island a tombolo is formed. An example of a tombolo is Chesil Beach
